Electrical system for wind driven generators



Feb. 28, 1939. E. M. CLAYTOR 2,148,804

ELECTRICAL SYSTEM FOR WIND DRIVEN GENERATORS Filed Feb. 25, 1958 PROPELLEE & sa e-name SPEED lNVENTOR fdward M C/aylar Patented Feb. 28, 1939 2,148,804

ELECTRICAL SYSTEM FOR WIND DRIVEN GENERATORS Edward M. Claytor, Anderson, Ind., assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Application February 23, 1938, Serial No. 191,938

4 Claims. (Cl. 290-44) This invention relates to the generation of eleccross curves A, B, C, etcf, are stable operating tricity by a. generator driven by a wind wheel or points. Curve No. I shows the power that the a wind operated propeller. generator can absorb from the propeller when It is an object of the invention to control the the generator is charging one battery. When 5 load on the generator in accordance with the the wind velocities are relatively low the propeller 5 power of the wind operating the propeller. More will deliver power illustrated by curves A, B and particularly it is an object to absorb a large C. It should be'noted that these curves are inamount of power from the propeller at high wind 'tersected near their maximum values by curve velocity and to economically absorb less power at No. I. This shows economic operation because low wind velocity. Since the power to be derived the generator absorbs almost all of the peak 10 from a wind operated propeller varies as the cube power developed by the propeller. of the velocity of the wind, it is evident that the If the wind velocity is increased more and more, most economical system is one inwhich the load causing the propeller to deliver greater output, on the generator is controlled in accordance with as shown by c s the genera-tor Wind velocity. When the wind velocity is low, absorbing ty, w th one batte y. is nsuflicient 5 the loading of the generator should be low, otherto take the peak D AS a result the Point f wise the propeller would be prevented from oboperati n is n th negative sl p p rt n of t taining an efficient speed. At high wind velocity p p ll r u put u v representing h p d the load on the generator should be increased in p ration and low power b orption.

order to prevent the propeller from running away I m r t a n battery is p a n charge 20 in high winds, and in order to take advantage of Connected in Series. When the d Ve the increase in power. reaches curve D, the new power absorbing curve In order to accomplish this object, the present o- 2 w l intersect D near its p This o ds invention provides for automatically changing the true for W d velocities much higher a that loading of the generators from one storage batep e ted y Velocities represented y 25 tery or group of cells to a plurality of batteries. Curves F A single battery or group of cell i used wh n These curves have been substantiated by a test the wind velocity is low. At a predetermined model d clearly indicate that m D can higher wind velocity, a wind operated swit h be absorbed over the whole range of wind velocitrols a circuit which effects the'connection of the ti s w n th p w absorbing a ty of t n- 30 generator with a plurality of batteries in series. orator is increased y increasing e umb of In this way the generator is loaded to prevent batteries in e s o a ethe propeller from attaining an excessive speed The means for automatically controlling the in a high wind; and a plurality of batteries ar load of .thegenerator in conformity with variaprovided for absorbing the excess energy of the t in Wind Velocity will now be described in generator. v reference to Fig. 1. In. Fig. 1, 20 designates a Further objects and advantages of the present generator driven by the wind wheel or p opeller invention will be apparent from the following O end of e Shunt field of the enerator description, referencebeing had to the accomand one of its brushes arev ounded at 22. The

panying drawing wherein a. preferred b other brush is connected by a wire 23 with a 40 ment, of the present invention is clearly shown. 'Switoh Contact 24 engageable w o able con- In the drawing: tact 25 mounted on the upper side of an armature Fi 1 i a wiring diagram of an electricalwir- 26, the lower side of which carries a contact 21 cult involving the present invention, engageable with 8. fixed contact 28. I The arma- 4 Fig. 215a chart of curves illustratingthe operature 26 i pi d at 29, and isvthere connected 4:; tion of t present in ent with a wire 30, resistance 3| and amagnet coil Referring to Fig.2, the base or horizontal line Coil 31 surrounds a core 33 etically rerepresents propeller d generator d, t lated to armature 26. Resistance 3| is connected vertical line represents horsepower. The various t0 the wire 23 and t0 Wire 34 connected to one curves from A, B, etc., to G are horsepower outte na of 1 Sto battery 35 having its other 50 put curves of the propeller for various air velocir terminal connected by wire 36 with contact 29. ties. Curve No. l represents the generator input The wire 30 is contacted with a cut-out relay when charging one battery. Curve No. 2 repre- 40 comprising an armature 4| pivoted at 42 and sents the generator input when charging two. urged by a spring 43 against a stop 44 and carbatteries. The points where the curves l'and 2' rying a contact 45 engageable with a contact 48. 5s

am I I closing position by magnet coil 58 which becomes.

Armature cooperates with a magnetizable core 41 surrounded by two magnet coils, namely, coil 68 which is an armature attracting coil, and 49 which is an armature holding coil. Coil 68 is grounded at 50. Contact 46 is connected by wire 5! with a storage battery 55 grounded at 56.

The parts 24, 29, 32 and 33 constitute a transfer switch 38 which either connects battery 55 alone with the generator or connects battery 55 in series 35 with the generator 28. The transfer switch 38 is controlled by a wind switch 50 which comprises a paddle or vane 5i, pivoted at 62, and urged by a spring 63"against a stop 55. Vane (it carries a contact 55 engageable with a contact 65 connected by wire 57 with the magnet coil 32 of transfer switch 38. Arrows 88 designate 'a current of wind which impinges upon the vane 5!. At relativelylow wind velocity, the switch contacts 65 and 66 are held open by the spring 53.

While the wind switch is open, the transfer switch will be inthe condition shown in Fig. .1 in which the battery 55 only is connected with the genera-'- tor 20 and the cut-out relay through the following circuit: generator 20, grounded at 22, wire 23, contact 26, contact 25, armature 25, wire 50, coil d9, armature ii, contact 55, contact liiywire 5!, battery 55 and ground 55. It will be understood that thereby armature M is attracted to circuit energized to affect the closing of contacts $5 and 15 when the generator voltage has attained a certain value.

When the velocity of the wind impinging upon the vane 5i has attained a certain value, the resistance of the spring 55 will be overcome, thereby permitting the contact. 55 to engage the contact 56. When this occurs the magnet coil 32 of the transfer switch 38 will be energized through i the following circuit: generator 20, grounded at 22,,wire 23, contact 26, contact 25, armature 26, coil 52, wire 57!, contact 55, contact 65, pivot 52 v and ground connection 59. Coil 32 being energized, armature 26 will be attracted toward core 33, thereby separating contact 25 from contact 24, and bringing contact 27 into engagement with contact 28. At the instant of separation of contact 21 from contact 25, there is a momentary rise of generator voltage whichis fed through resistor 3! to the shunt coil 48 of the cutout'relay 40 during the time the armature 26 of the transfer switch 38 is operating. This prevents the cutout relay from opening while the transfer switch armature 25 moves from contact 24 to contact 28.

The resistor 3| prevents short circuit of battery 35 and has practically the same amount of resistance as magnet coil 48 which is across battery 55 during charge;

The closing of contacts 27 and 28 and the separation of the contacts 24 and 25 causes both batteries 35 and 55 to be connected with'in'series with the ground through the following circuit: generator 20, grounded at 22, wire 23, wire 34, battery 35, wire 36, contact 28, contact 21, armature 25, wire 30, cutout relay 40, wire 5|, battery 55 and ground connection. In this manner the wind switch 60, which is affected by the same breeze which operates the propeller 2i, acts through thetransfer switch 38 to change the generator out-putfrom that represented by curve No. i of Fig. 2, to the out-put represented by curve No. 2, when the wind velocity has attained a certain value.

' When the wind velocity decreases below a certain value the wind switch 60 will open, and the transfer switch willbe restored to normal position shown in Fig. l, by a spring 26a. which biases the armature 26 upwardly.

The field coil of the generator in this system is liberallydesigned to withstand the increased loss-in it when charging more batteries in series.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be. adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. An electrical system for wind driven generators comprising, a wind propeller operated generator, a plurality of batteries of storage cells, and control means responsive to wind velocity for connecting alower number of battery cells with the generator at relatively low wind velocity and a higher number of battery cells in series with the generator at higher wind velocity.

2. An electrical system according to claim 1 in which the control means includes a transfer switch for including a lesser or a greater number of battery cells in series with the generator, and

a wind operated switch for controlling the operation of the transfer switch.

3. An electrical system according to claim 1 in which a cut-out relay is in circuit between the generator and storage battery and in which a circuit is provided for keeping a voltage on the magnetically operated transfer switch for in cluding a lesser or a greater number'of battery cells in series with the generator, and a wind operated switch for controlling the energization of the magnet of the transfer switch.

EDWARD M. CLAYTOR. 

